1. Microsoft Visual Basic 2005 BASICSyo
Microsoft Visual Basic 2005 BASICS
Lesson 7
Strings and Decimal Types

2. Objectives Declare string variables. Assign text to string variables.yo
Objectives
Declare string variables.
Assign text to string variables.
Concatenate strings.
Use decimal data types.
Use the Format function.
Microsoft Visual Basic 2005 BASICS

3. Objectives (cont.) Use the Enabled property.yo
Objectives (cont.)
Use the Enabled property.
Use the SelectionStart and SelectionLength properties.
Microsoft Visual Basic 2005 BASICS

4. Declaring String Variablesyo
Declaring String Variables
Text is often called alphanumeric data.
Can include letters or numbers
Data types that hold text are usually referred to as strings.
When you declare a string, the resulting variable can hold a string of any practical length.
Microsoft Visual Basic 2005 BASICS

5. Assigning Text to String Variablesyo
Assigning Text to String Variables
Place the text in quotation marks.
Hard-coded text is called a string literal.
Like a numeric variable, a string variable can only hold one string.
Each time you assign a string to a string variable, the existing data is replaced.
Microsoft Visual Basic 2005 BASICS

6. Assigning Text to String Variables (cont.)
Microsoft Visual Basic 2005 BASICS

7. Assigning Text to String Variables (cont.)
Microsoft Visual Basic 2005 BASICS

8. Concatenation Concatenation Ampersand (&)yo
Concatenation
Concatenation
Appends one string to the end of another
Ampersand (&)
You can concatenate more than two strings in one expression.
You can also use concatenation when creating the text for a label.
Microsoft Visual Basic 2005 BASICS

9. Concatenation (cont.)
Microsoft Visual Basic 2005 BASICS

10. Concatenation (cont.)
Microsoft Visual Basic 2005 BASICS

11. Concatenation (cont.)
Microsoft Visual Basic 2005 BASICS

12. Concatenation (cont.)
Microsoft Visual Basic 2005 BASICS

13. Using Decimal Types Single data type Double data typeyo
Using Decimal Types
Single data type
Used for decimal values that will not exceed 38 digits
Double data type
Used for decimal values with more than 38 digits
Decimal data type
Used to work with dollars and cents
Microsoft Visual Basic 2005 BASICS

14. Using the Format Functionyo
Using the Format Function
The Format function
Allows you to apply custom formatting to a number before displaying the value
The Format function can be used to format decimal values, phone numbers, and more.
Microsoft Visual Basic 2005 BASICS

15. Using the Format Function (cont.)
Microsoft Visual Basic 2005 BASICS

16. Using the Format Function (cont.)
Microsoft Visual Basic 2005 BASICS

17. Using the Format Function (cont.)
Microsoft Visual Basic 2005 BASICS

18. Using the Enabled Propertyyo
Using the Enabled Property
Enabled property
Makes a control take on a grayed appearance that makes it inactive but still visible
Objects that are inactive can be seen by the user, but will not respond to user actions.
Microsoft Visual Basic 2005 BASICS

19. Using the Enabled Property (cont.)
To disable an object, set the Enabled property to False.
Microsoft Visual Basic 2005 BASICS

20. Using the SelectionStart and SelectionLength Propertiesyo
Using the SelectionStart and SelectionLength Properties
SelectionStart property
Specifies the location where the insertion point will be inserted when the text box gets the focus
SelectionLength property
Specifies how many characters should be selected to the right of the cursor
Microsoft Visual Basic 2005 BASICS

21. Using the SelectionStart and SelectionLength Properties (cont.)
Microsoft Visual Basic 2005 BASICS

22. Summary Strings hold text or alphanumeric data.yo
Summary
Strings hold text or alphanumeric data.
Visual Basic has a data type for strings.
Text assigned to a string variable must be placed in quotation marks.
You can use the assignment operator to assign text from a text box to a string variable or from a string variable to another string variable.
Microsoft Visual Basic 2005 BASICS

23. yo
Summary (cont.)
Concatenation is the process of appending one string to the end of another.
The ampersand (&) is the symbol used for concatenation.
The Single, Double, and Decimal data types hold decimal data.
The Decimal data type is specially designed for handling dollars and cents.
Microsoft Visual Basic 2005 BASICS

24. yo
Summary (cont.)
The Format function uses a string of symbols to format decimal values, phone numbers, and more.
The Enabled property is used to make a control inactive or active.
The SelectionStart and SelectionLength properties and the Len function can be used together to highlight the text in a text box.
Microsoft Visual Basic 2005 BASICS